Roumain was born in Puerto Rico and worked as interior designer for several years before she decided to become an actress. She started as model and filmed television commercials and shot print ads for companies such as Mercedes Benz, Disney, Great Call, Walmart, Volkswagen, Nissan, US Air Force, Coca Cola, Verizon, and California Avocado. Among her early acting credits are the short films Never Land (2000), Wounded Love (2004), Brooklyn's Bridge to Jordan (2005), and Displaced Aggression (2007) as well as a featured role in the comedy Jersey Girl (2004, with Stephen Root and Mike Starr).

Further acting work includes the short drama Lily (2010), the short film L.A. Vampire (2010, with Paul Rae), the drama Go for It! (2011, with Peipei Yuan), and the television mini series Little Shrink (2012).

More recently, Roumain had supporting roles in the thriller Shadow of the Monarch (2013) and the thriller The Guest House (2013, with Billy Mayo and Andray Johnson).